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A297903
Number of nX4 0..1 arrays with every element equal to 0, 1, 3 or 4 king-move adjacent elements, with upper left element zero.
1
5, 13, 4, 37, 54, 97, 466, 1105, 3354, 12282, 37107, 122676, 416828, 1349661, 4501298, 15041029, 49602808, 165300728, 550279764, 1824434359, 6073061606, 20198360858, 67084559733, 223165737677, 742040901128, 2466100981652, 8201311431601
OFFSET
1,1
COMMENTS
Column 4 of A297907.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +3*a(n-2) +37*a(n-3) -72*a(n-4) -91*a(n-5) -511*a(n-6) +996*a(n-7) +1127*a(n-8) +3714*a(n-9) -7300*a(n-10) -7764*a(n-11) -16505*a(n-12) +32748*a(n-13) +33291*a(n-14) +48840*a(n-15) -96768*a(n-16) -94276*a(n-17) -101571*a(n-18) +195114*a(n-19) +183178*a(n-20) +153514*a(n-21) -271344*a(n-22) -250136*a(n-23) -171491*a(n-24) +257601*a(n-25) +242029*a(n-26) +141857*a(n-27) -160048*a(n-28) -163417*a(n-29) -85103*a(n-30) +56777*a(n-31) +72364*a(n-32) +33825*a(n-33) -4557*a(n-34) -16800*a(n-35) -5732*a(n-36) -4294*a(n-37) -610*a(n-38) -1765*a(n-39) +1011*a(n-40) +1344*a(n-41) +1068*a(n-42) +241*a(n-43) -214*a(n-44) -147*a(n-45) -78*a(n-46) -4*a(n-47) -2*a(n-48) for n>51
EXAMPLE
Some solutions for n=7
..0..1..0..1. .0..1..1..1. .0..1..1..1. .0..0..0..1. .0..1..1..1
..0..1..0..1. .1..1..0..0. .1..0..1..1. .0..0..1..0. .1..1..0..0
..1..1..0..0. .0..1..0..0. .0..0..0..0. .1..1..1..1. .0..1..0..0
..1..1..0..1. .1..0..1..1. .1..0..1..1. .0..0..1..0. .0..1..1..0
..0..1..0..0. .0..0..1..1. .1..0..1..1. .0..0..0..1. .0..0..1..0
..1..1..0..1. .1..0..1..0. .0..0..0..1. .1..1..1..1. .1..0..1..1
..1..1..0..1. .1..0..1..0. .1..0..1..0. .0..0..1..0. .1..0..1..1
CROSSREFS
Cf. A297907.
Sequence in context: A088618 A121645 A057691 * A298497 A246922 A246921
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 08 2018
STATUS
approved